Up to 40% of northeastern Asians experience flushing and elevated heart rate after drinking even minimal amounts of alcohol, due to accumulation of acetaldehyde. This is because of a mutation in acetaldehyde dehydrogenase (ALDH2), the enzyme that converts acetaldehyde to acetate.
When you use Outlook, the operating system saves your files in the \Documents and Settings\ directory for your user name. This directory saves some user-specific configurations, including the contact files used in your Outlook installation. Each Outlook file can be identified by its extension. Contacts are saved with the \.pab\ file extension.
A .dat file is often a file from a popular application that got its extension changed by Outlook, the computer or the copier that saved the file. When receiving a .dat file, try to think what kind of file it could be: a Word doc, an Excel file, a Powerpoint file, an Adobe .pdf or a scanned jpg? According to your estimation, try to change the extension to the expected extension and see if you can open it.